The ability to control the behaviour of individual cells has long been a goal of scientists studying cell development. MIT researchers have now developed a method to manipulate how a single cell moves and changes shape, using light. This breakthrough, which could have far-reaching applications in synthetic biology and medicine, was demonstrated in egg cells from starfish—a common model for understanding cell behaviour during development.

The team, led by Nikta Fakhri, focused on an enzyme within the starfish egg cell that triggers a cascade of movements. By genetically engineering a light-sensitive version of this enzyme, the researchers were able to use light to direct the cell’s motion in precise patterns.

“We found that the light successfully triggered the enzyme, which in turn prompted the cells to jiggle and move in predictable patterns,” says Fakhri, an associate professor of physics at MIT. “For instance, we could stimulate cells to exhibit small pinches or sweeping contractions, depending on the pattern of light we induced. We could even shine light at specific points around a cell to stretch its shape from a circle to a square.”

The findings, set to be published in Nature Physics, open up exciting possibilities for future medical and synthetic cell applications. The researchers envision using this technology to design cells that could respond to light for therapeutic purposes, such as “patch” cells that contract to help close wounds or drug-delivering cells that release medication only when illuminated at specific locations in the body.

Fakhri continues, “By revealing how a light-activated switch can reshape cells in real time, we’re uncovering basic design principles for how living systems self-organize and evolve shape.”

The research team includes MIT’s Jinghui Liu, Yu-Chen Chao, and Tzer Han Tan, alongside collaborators from Ludwig Maximilian University of Munich, Saarland University, and the Whitehead Institute for Biomedical Research.

Exploring the Starfish Model

Fakhri’s group specializes in understanding the physical dynamics that drive cell growth, especially the role of symmetry in cell development. The starfish, known for its distinct stages of symmetry, is an ideal organism for studying the signalling processes that guide cell organization.

“A starfish is fascinating because it starts with a symmetrical cell and eventually develops into an adult with pentameral symmetry,” Fakhri explains. “There are many signalling events along the way that direct how the cell organizes itself into more complex structures.”

The team’s earlier research identified a key “circuitry” in the starfish egg cell that regulates its movement and shape. This circuitry involves an enzyme called GEF, which, when activated, triggers a protein called Rho. Rho plays a crucial role in regulating cell mechanics by binding to the cell’s membrane and initiating the formation of muscle-like fibres that enable the cell to contract and move.

Harnessing Light to Control Cell Movement

In this new study, the team turned to optogenetics, a technique that uses light to control genetically engineered cellular components. They created a light-sensitive version of the GEF enzyme and injected it into egg cells harvested from starfish. The cells, now capable of producing the light-sensitive enzyme, were placed under a microscope, and the researchers applied light in different patterns to observe how the cells responded.

By targeting specific areas of the cell with light, they were able to activate the enzyme, triggering the Rho protein to form fibers and cause the cell to move. This allowed the team to control the cell’s shape, even morphing it from a circle into a square. Additionally, they discovered that shining light in a single spot could initiate sweeping contractions within the cell, providing even more precise control over its behaviour.

“We realized this Rho-GEF circuitry is an excitable system, where a small, well-timed stimulus can trigger a large, all-or-nothing response,” Fakhri says. “By illuminating either the entire cell or just a small region, we can control how the cell responds and causes contraction or pinching.”

The researchers also developed a theoretical framework to predict how cells would change in response to light stimuli. This new understanding of cellular “excitability” could have important implications for fields like developmental biology, wound healing, and synthetic biology.

Future Applications in Synthetic Biology

“This work provides a blueprint for designing programmable synthetic cells,” Fakhri explains. “By controlling cell shape in real time, we can potentially design cells that perform specific tasks in the body when activated by light. This could lead to new biomedical applications, from targeted drug delivery to tissue repair.”

The ability to control cell behaviour with light opens up exciting possibilities for future research and applications, offering a new way to explore how cells shape themselves during development and how we might harness these processes for therapeutic use.

Quantum computers have the potential to solve complex problems that current classical supercomputers cannot. As quantum technology progresses, a key challenge is developing effective ways for quantum processors to communicate with each other efficiently. Traditional methods for interconnecting superconducting quantum processors use “point-to-point” connections, which are limited by error rates that increase as more transfers occur. MIT researchers have taken a major step toward overcoming these limitations by developing a new interconnect device that supports scalable, “all-to-all” communication between quantum processors.

The breakthrough, described in a paper published in Nature Physics, involves a network of two quantum processors linked by an interconnect that sends microwave photons—particles of light that carry quantum information—back and forth on demand. The device includes a superconducting waveguide that can shuttle photons between processors and allows for the coupling of multiple modules, enabling more efficient information transfer across a scalable network.

“In the future, a quantum computer will probably need both local and nonlocal interconnects. Local interconnects are natural in arrays of superconducting qubits. Ours allows for more nonlocal connections. We can send photons at different frequencies, times, and in two propagation directions, which gives our network more flexibility and throughput,” said Aziza Almanakly, the lead author of the paper and a graduate student in MIT’s Engineering Quantum Systems group.

This interconnect device is a significant advancement in the quest to build a distributed network of quantum processors. By generating remote entanglement—quantum correlations between distant processors—it paves the way for a large-scale, interconnected quantum computing system.

“Pitching and catching photons enables us to create a ‘quantum interconnect’ between nonlocal quantum processors, and with quantum interconnects comes remote entanglement,” said senior author William D. Oliver, a professor of Electrical Engineering and Computer Science at MIT. “Generating remote entanglement is a crucial step toward building a large-scale quantum processor from smaller-scale modules.”

The researchers achieved this by connecting two quantum modules, each composed of four qubits that interface with the waveguide to emit and absorb photons. By using carefully timed microwave pulses, they directed photons to propagate through the waveguide in either direction, establishing remote entanglement between two modules. This entanglement allows quantum operations to occur across distant, disconnected processors.

“We can use this architecture to create a network with all-to-all connectivity. This means we can have multiple modules, all along the same bus, and we can create remote entanglement among any pair of our choosing,” explained Beatriz Yankelevich, a graduate student and co-author of the paper.

One of the major hurdles in quantum communication is ensuring the photon is absorbed with high efficiency at the receiving module. To tackle this, the team used a reinforcement learning algorithm to optimize the photon’s shape, improving the absorption efficiency to over 60 percent. This efficiency is enough to confirm that the entanglement is successful—a critical milestone in building a robust quantum network.

This development could eventually lead to advancements in quantum internet systems, where quantum processors across vast distances can share information securely. While this demonstration marks a significant achievement, the team envisions further refinements, such as optimizing photon propagation paths and reducing protocol errors.

“In principle, our remote entanglement generation protocol can also be expanded to other kinds of quantum computers and bigger quantum internet systems,” Almanakly said, hinting at the vast potential for this technology to shape the future of computing.

As quantum networks continue to evolve, this research could be a foundational step toward realizing a new era of distributed quantum computing

A team led by researchers at MIT has detected pyrene, a complex carbon-containing molecule, in a distant interstellar cloud. This finding opens new avenues for understanding the chemical origins of our solar system. Pyrene, a type of polycyclic aromatic hydrocarbon (PAH), was found in a molecular cloud similar to the one from which our solar system formed.

This marks the first time a complex form of carbon essential for life on Earth has been observed outside the solar system. Its discovery sheds light on how the compounds necessary for life could originate in space. The team detected pyrene in
a star-forming region known as the Taurus Molecular Cloud, located 430 light-years away, making it one of the closest such clouds to Earth.

This discovery also aligns with recent findings from the asteroid Ryugu, suggesting that pyrene may have played a key role in the carbon composition of the early solar system. To learn more about the significance of this discovery, EdPublica interviewed the researchers behind the study– Gabi Wenzel, Ilsa Cooke, and Brett McGuire, who shared their insights on the implications of pyrene’s presence in space and its potential impact on our understanding of star and planet formation. Brett McGuire is an assistant professor of chemistry at MIT, Ilsa Cooke is an assistant professor of chemistry at the University of British Columbia, and Gabi Wenzel is a postdoctoral researcher in McGuire’s group at MIT.

Below, the team responds to questions from EdPublica Editor Dipin Damodharan about this unexpected and exciting discovery.

‘Pyrene could be a major source of carbon in our solar system’

Q: How does the discovery of pyrene in TMC-1 enhance our understanding of the chemical inventory that contributed to the formation of our solar system?

Gabi Wenzel:

Stars much like our own sun are born from dense molecular clouds. The discovery of pyrene in a molecular cloud called TMC-1, one that might be very similar to our sun’s natal cloud and which will go on to form a star of its own, significantly enhances our understanding of the chemical inventory that contributed to the formation of our own solar system. As a polycyclic aromatic hydrocarbon (PAH), pyrene is one of the most complex organic molecules found in early molecular clouds, suggesting that the building blocks of organic matter were available in the environments where stars and their orbiting (exo)planets form.

This discovery sheds light on the chemical processes occurring in interstellar space, including gas-phase and surface reactions on dust grains, which are crucial for the evolution of organic chemistry. This further supports the notion that the primordial materials of our solar system contained a diverse range of organic compounds, providing insights into the potential for prebiotic chemistry on a young Earth and planetesimals.

Q: What specific challenges did you face in detecting pyrene, given that it is invisible to traditional radio astronomy methods, and how did the use of cyanopyrene help overcome these challenges?

Gabi Wenzel:

Pyrene, a fully symmetric PAH, does not possess a permanent electric dipole moment and hence is invisible in radio astronomical observations or rotational spectrometers in the laboratory. The CN radical is highly abundant in the cold and dark molecular cloud TMC-1, an environment that is about 10 K cold and in which you’d assume little chemistry to happen. However, earlier experimental works have shown that the CN addition (followed by hydrogen abstraction) to ringed hydrocarbon species such as benzene and toluene at low temperatures is a barrierless process.

Adding a CN (nitrile) group to a hydrocarbon will drastically increase its permanent electric dipole moment and so allow rotational transitions. Indeed, several CN-functionalized species have been detected in TMC-1 and other sources, among which the CN-substituted benzene (cyanobenzene or benzonitrile) and other smaller PAHs, with cyanopyrene being the largest molecule found via radio astronomy to date, allowing us to infer the presence of pyrene itself.

Q: Can you elaborate on what it means for our understanding of carbon sources in the solar system that pyrene is found in both TMC-1 and asteroid Ryugu?

Ilsa Cooke:

TMC-1 is a famous example of a cold molecular cloud, one of the earliest stages of star and planet formation, while asteroids like Ryugu represent snapshots of later stages in the formation of solar systems. Asteroids are formed from material in the solar nebula that was inherited from the molecular cloud stage. Our radio observations of TMC-1 let us observe pyrene early on and possibly under conditions where it is first forming. Isotope signatures of the pyrene in Ryugu suggest it was formed in a cold interstellar cloud. From these two unique sets of measurements, we can start to unravel the inheritance of pyrene, and PAHs more generally, from their birth in interstellar space and their journey to new planets. If PAHs can survive all the way from the molecular cloud stage, they may provide planets with an important source of organic carbon.

Q: What are the different formation routes of PAHs that your research suggests, and how do these differ from previous hypotheses about PAH formation in space?

Ilsa Cooke:

Our results, combined with those of Zeichner et al., who measured pyrene in Ryugu, suggest that pyrene may form at low temperatures by “bottom-up” routes in molecular clouds. Previously, PAHs were most commonly associated with formation in high-temperature (ca. 1000 K) environments in the envelopes of dying stars. These stars are thought to eject their PAHs, along with other carbon-rich molecules, into the diffuse interstellar medium.

However, the diffuse medium is a tenuous, harsh environment permeated by ultraviolet photons, and most astrochemists think that small PAHs would not survive their journey through the diffuse medium into dense molecular clouds. So we are still left with a puzzle: does that pyrene that we observe in TMC-1 form there, or was it formed somewhere else but it was able to survive its journey more efficiently than previously thought? If the pyrene is indeed formed within TMC-1, we do not yet know the chemical mechanism. Many possibilities exist, so close collaborations between laboratory astrochemists and observers will be critical to answer this question.

Q: What are your plans for investigating larger PAH molecules in TMC-1, and what specific hypotheses are you looking to test with these investigations?

Brett McGuire:

We have a number of other targets lined up – again focusing on PAH structures that should show this special stability demonstrated by pyrene. They present the same experimental challenges, including needing to devise appropriate synthetic routes in the laboratory before collecting their spectra. The major question is just how complex the PAH inventory actually gets at this earliest stage of star formation.

Prior to our work in TMC-1, nearly everything we knew about PAHs came from infrared observations of bulk properties in much warmer and more energetic regions, where PAHs are thought to be much larger. Does the population in TMC-1 look the same as in these regions? Is it at an earlier stage of chemical evolution? And how does this distribution compare to what we see in our own Solar System?

Q: How do your findings about pyrene and PAHs in interstellar clouds influence our broader understanding of organic chemistry in the universe, particularly in relation to the origins of life?

Brett McGuire:

Life as we know it depends on carbon – it is the backbone upon which all our molecular structures are constructed. Yet, the Earth overall is somewhat depleted in carbon relative to what we’d naively expect, and we still don’t fully understand where the carbon we do have came from originally. PAHs in general seem to be a massive reservoir of reactive carbon, and what we are now seeing is that that reservoir is already present at the earliest stages of star-formation. Combined with the evidence from Ryugu, we’re now also seeing indications that the inventory of PAHs, and thus this reservoir of carbon, may actually survive from this dark molecular cloud phase through the formation of a star to be eventually incorporated into the planetary system itself.